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Exhibit 21

As of 12/31/03

LIST OF SUBSIDIARIES OF CHIRON CORPORATION

SUBSIDIARY						JURISDICTION OF INCORPORATION OR ORGANIZATION
Cetus Generic Corporation						Delaware, USA
Chiron Partners, Inc.						California, USA
Chiron Alpha Corporation						California, USA
Chiron/Cephalon JV (50%)						Delaware, USA
Chiron Properties, Inc.						California, USA
Chiron Delta Corporation						Delaware, USA
Chiron Investment Corporation						Nevada, USA
Chiron Mimotopes U.S.						California, USA
Chiron Redevelopment Corporation						Missouri, USA
Chiron Foreign Sales Corporation						U.S. Virgin Islands
Biocent Insurance Company, Inc.						Hawaii, USA
Chiron AB						Sweden
Chiron Vision Canada, Inc.						Canada
Chiron Behring Vaccines Private Limited (51%)						India
Chiron Technologies Pty. Ltd.						Australia
Chiron B-1 Limited1						Bermuda
Chiron Overseas Holding Co.						Nevada, USA
	Chiron B-2 Limited1					Bermuda
		Chiron Blood Testing (Bermuda) Ltd. (Originally formed as a limited liability company; converted into a partnership on 12/18/02)				Bermuda
		PathoGenesis Portugal—Produtos Farmacêuticos, Sociedade Unipessoal Lda.				Portugal
		Chiron Corporation Limited				United Kingdom
		Chiron B.V.				The Netherlands
			Cephalon Chiron B.V.			The Netherlands
			Chiron Blood Testing B.V.			The Netherlands
		Chiron Canada ULC/Chiron Canada SRI				Canada
		Chiron Italia S.r.l				Italy
		Chiron France S.A.S.				France
		Chiron Blood Testing S.a.r.l.				France
		Chiron Limited				Hong Kong
		Chiron UK-1 Limited (Formerly known as "Alnery No 2339 Limited", name changed effective May 9, 2003)				United Kingdom
			PowderJect Pharmaceuticals Limited (formerly plc)			United Kingdom
				Circassia Ltd.		United Kingdom
				Chiron Vaccines Australia Pty Ltd.		Australia
				Evans Vaccines Ltd.		United Kingdom
				EPS Vaccines Ltd.		United Kingdom
				PowderJect Pharmaceuticals Employees Share Scheme Trustees Ltd.		Jersey
				PowderJect Research Ltd.		United Kingdom
				PowderJect Technologies BV		The Netherlands
					AlgoRx Pharmaceuticals Inc. US (13%)	United States (Delaware)
					Bavarian Nordic AS (6%)	Denmark

					PowderChek Diagnostics Inc.	United States (Delaware)
				SBL Vaccin AB		Sweden
					Vitec AB	Sweden
				PowderJect Technologies Ltd.		United Kingdom
				PowderJect Therapeutics Inc.		United States (Delaware)
PowderJect Vaccines Inc.						United States (Delaware)
	Chiron Healthcare Ireland Limited dba "Chiron Ireland"					Ireland
		Chiron Blood Testing Pty Ltd				Australia
	Appold Consultadoria E Serviços Lda					Portugal
		Chiron Holding LLC (Formerly known as "Chiron LLC")				Delaware
		Chiron Hungary Üzleti Szolgáltató Korlátolt Felelösségü Társaság (aka Chiron Hungary Kft.) or Chiron Hungary Business Services Limited Liability Company (aka Chiron Hungary Ltd)2				Hungary
		Chiron Vaccines Holding Srl (formerly known as "Ami' Centro Srl")3				Italy
			Chiron Srl (formerly known as S.p.A.)			Italy
				Istituto Vaccinogeno Pozzi Srl (formerly known as S.p.A.).		Italy
			Chiron Funding LLC (0.01%)			Delaware, USA
			Chiron Corp. s.r.o. [75%; Chiron Vaccines International & Co KG, 25%]			Czech Republic
		Chiron Vacccines International Srl & Co KG (formerly known as "Chiron Redevelopment Corp. & Co. KG")				Germany
				31. Corsa Verwaltungsgesellschaft mbH		Germany
				Chiron Behring Verwaltungsgesellschaft mbH		Germany
				Chiron Behring GmbH & Co4		Germany
				Chiron GmbH		Germany
		Chiron Investment Company Spain, Srl (ETVE)				Spain
Chiron Iberia S.L.						Spain

¹

Chiron B-1 Limited and Chiron B-2 Limited entered into a partnership called Chiron Blood Testing (Bermuda) Ltd. on 12/18/2002; Chiron B-1 holds an 85% partnership interest, and Chiron B-2 holds a 15% partnership interest. Together, the 2 entities jointly own Chiron Blood Testing (Bermuda) Ltd. and the subsidiaries listed thereunder.

²

Appold holds a 99.4% interest and Chiron Holding LLC holds a 0.6% interest.

³

Appold holds a 94% interest and Chiron Holding LLC holds a 6% interest.

⁴

Chiron Redevelopment Corp & Co KG holds a 99% interest and Chiron Behring holds a 1% interest.

2

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Exhibit 21

LIST OF SUBSIDIARIES OF CHIRON CORPORATION